Down the Rabbit Hole
by Tyger Elf
Summary: This is a What If AU of Knockout. She is Alice and this case is her rabbit hole. And despite its madness, at least Wonderland will have answers for her.


_This came from a prompt posted on Tumblr at castlefanficprompts. In order to avoid ruining the surprise, the prompt is posted at the end of the fic. Also, a heads up is in order because I didn't do as much proofreading as I should have since I was anxious to post this. If you catch something, please let me know!_

* * *

Kate paces back in forth, wall to wall. Every time she passes her window, she looks at her shutters. She knows – she _knows_ she is missing something. So she stares at her makeshift murder board longer and harder every time she passes it. If she should just find one piece of information, then she knows everything would fall into place. She just needs _one piece_. There is the phantom taste of answers and justice in the back of her throat, but that's all this is. All _he_ is, all _they_ are. The Dragon, a ghost. Lockwood, a ghost. And she can't find any answers, there's nothing there, nothing, no matter how long or how hard or how often she looks, _there is nothing there_.

Kate wants to scream and rage at how unfair everything is, but her maudlin thoughts are interrupted when she hears someone knocking on the door. She knows it's probably Castle because throughout this whole case he's been looking at her like she might break or fly off the handle (probably both, if they're both honest). But even if she is nearly sure it's her partner, she's still not stupid enough to answer the door unarmed; so she grabs her gun on the way to the door.

She opens it carefully, not that a slow-moving door would deter an armed assassin. But it still makes her feel better, still makes her feel like she can control something when everything else is spiraling away from her. When she confirms that Castle is indeed knocking on her door, she opens the door wider.

For a second, they stare at each other. Kate feels like a chasm is growing between them, that it'll be too wide to cross soon. She swallows hard and shakes those feelings away because she can only deal with so many crises at a time, and her feelings for Castle are just going to have to take a backseat for a few days.

"Can I come in?" Castle asks after the pause has gone on a little too long. Kate's eyes flicker down, deciding, but she knows she is falling apart and needs help.

"Yeah," she tells him, stepping back for him to enter her apartment. Maybe he will offer up some insight, some wild theory that will help her solve this puzzle and end this fight. Instead, he starts talking, going on and on. He confirms the third man theory, and tells her that Ryan and Esposito are looking in records.

She narrows her eyes at this. She needs answers, actual _answers._ She doesn't need him wasting her time. "Castle, you couldn't have just called me and old me this over the phone?" She's irritated, but she tries her damnedest to suppress the urge to bite his head off because she knows he is just trying to help. _But this isn't helping; he is wasting your time_ , a voice in the back of her mind whispers.

He opens his mouth to answer, and says that he could have called her. Then he starts stuttering and mumbling, and he has never been at a loss for words. She's thinking he may have bad news, something came up and they can't investigate. Or maybe, _god forbid_ , someone else has died.

So, she opens her mouth to tell him to spit it out. "Castle, if you've got somethin' to say, just say it."

She can see in his face that his is building up the courage to tell her something that she probably won't like. "Castle, everyone associated with this case is dead. Everyone." Kate feels the breath leaving her lungs because _like hell_ does she need reminding that this people killed _her mother_ , but Castle continues speaking. "First your mom and her colleagues. Then Raglan and McAllister. You _know_ they're comin' for you next."

She stops him right there because she knows exactly where this little speech is going. She has heard it a dozen times (the sheer number of times she has been told to stop should have been her first clue), and she is sick and tired of it. "Captain Montgomery's got a protective detail on me," she says, dismissing his concerns. "It wasn't that hard to spot." And besides which, she is capable of taking care of herself. She does not need him to be her knight in shining armor.

Apparently, Castle isn't done, though. "That's not gonna be enough to stop Lockwood, you know that. Think about what they're up against. Professional killers?" he tells her. She can hear a tinge of desperation leaking into his voice, but she tries to ignore it. If he isn't going to help her, then he can just leave.

Castle just keeps talking; he just can't shut up tonight. "I've been working with you for three years. You know me, I'm the guy who says we can move that rubber tree plant, but you know what, Beckett? I don't think we're gonna win this."

Kate feels like he doesn't even understand. If she could just make him understand that this is her _mother_ they're talking about. This isn't a stranger who died tragically or too soon or with unfinished business. This isn't just some woman off the streets who was killed as a result of some random, wayward event. This is the woman who would sit with her when she was sick and watch _Temptation Lane_ with her, even though they both knew the show was so cheesy. This is the woman who listened to her heartbreaks over boys and listened to her complain about her father and helped raised her. Maybe, maybe he just doesn't understand that, but maybe she can tell him. "Castle, they killed my mother. What do you want me to do?" She thinks he'll understand if she just explains to him the significance of this case and how much it means to her.

"Walk away."

Two words and she feels like she's been sucker punched. This man has known her for three years, and he wants her to _walk away_? From her _mother_? Is he out of his mind? But to add insult to injury, he won't shut up. He just keeps talking, keeps digging the knife in deeper.

"They're gonna kill you, Kate. If you don't care about that, at least think about how that's going to affect the people that love you. You really want to put your dad through that? And what about Josh?" Castle says desperation now obvious. Kate doesn't even hear it, though. She's too busy seeing red because she is beyond furious that he would even _dare_ ask her these questions.

Kate is so angry, in fact, that she doesn't think about the words that come out of her mouth next. "What about you, Rick?" she asks him. She's so worked up that she is just daring him to cross that line in the sand.

But instead of replying to her question – instead of peacefully bowing out like he's done for the entirety of their partnership – he takes two long strides until he is standing toe-to-toe with her. For a split second, she idly wonders how she could forget his sheer size. Because, really, he is huge and so much bigger –

Then, she is distracted from Castle's size because his lips are on hers. One of his hands is sliding into her hair, gripping fiercely. His other hand wraps around her back and pulls her into his body. She thinks – not that he's making it easy – that he is trying to hold on a tightly as he can because he can feel the walls closing in on them. Maybe he knows that she is Alice and this case is her rabbit hole; maybe he knows that she can't help from wanting to go to Wonderland because, despite its madness, at least Wonderland will have answers.

Kate's line of thought falls away when Castle's tongue slips into her mouth, and she lets out a gasp into the silence of her apartment. She takes this time to slide her hands into his hair, and he pulls a moan from her. Really, this kiss is reminiscent of the one in the alleyway because there is still desperation.

Abruptly, Castle pulls away. He dips his head so that their foreheads are resting together. His hands remain in her hair and around her waist, but her slip down to rest on his shoulders. They are both panting into the silence of her apartment, and she doesn't know what to say. Usually he fills the silence between them.

"Castle," she murmurs, reaching up to tug on his hair.

His head jerks away from hers, and part of her misses the warmth of their bodies leaning on each other. "Kate," he gasps out, and she sees now that he didn't say anything earlier because he was trying to control his own emotions. His eyes are glistening, and his brow has a deep furrow. "Kate," he says again, "I can't lose you. I can't, okay?" His voice is thick, and he swallows hard. She tracks the movement of his throat with his eyes before returning to his gaze. When their eyes meet again, both of his hands move to cup her face. He leans in and kisses her again, this time softly. Castle pulls away slowly, and thumbs her cheeks. It takes her longer than it should to realize he's wiping away her tears because she doesn't know when she started crying.

Everything feels like it is completely spirally down, and she doesn't know how to stop it or even if she can.

"I can't stop, Castle," she tells him, wrapping her hands around his wrists and rubbing her thumbs across the back of his hands. "But I can't – can't lose you either." Oh, she's crying again, Kate realizes.

Castle takes his hands off Kate's face. He bands one across her upper back and uses the other to guide her head to the juncture of his shoulder and neck. She goes willingly, pulling her arms in to rest between the two of them. Without her usual heels, she fits so neatly into him. If Kate believed in all the things her partner did, she might be tempted to say that the Fates were sending her a sign.

"Kate, I won't let you fight this battle by yourself. But you can't try and push everyone away, okay?" he tells her. He presses his lips into her hair.

Kate burrows into Castle. She can't stop, but she can't lose Castle. She feels like she's drowning.

"We'll figure this out, Kate. I promise. But you need to back down, you need to just stop investigating because they are going to come for you and they will kill you."

Kate pulls back to look at him, forcing his hands to her shoulders. Her eyes are rimmed red, and there are tears tracks on her cheeks. "I don't know _how_ to stop, Rick. I've tried before, but every time I fall back down the rabbit hole like time hasn't even passed."

"Then I'll help you, Kate," he whispers. He leans in to kiss her again, just a brush of their lips. When he pulls away, Kate surges into him, pushing onto her toes. Her body feels electrified, and she doesn't want to lose this connection between them.

She pulls back, panting. "Promise, Castle?" There's a minute quirk to her lips that let's Castle know that Kate knows he will always have her back. But words have always been his forte in this dance of theirs.

"I promise, Kate. Always."

* * *

 _The prompt was this: 3X24, What if Castle to the "What about you Rick" of Beckett answered with a kiss?_

 _I did not intend for this to turn out quite as angsty as it did, but I fully blame that on the_ Grey's Anatomy _I was watching before I started writing this. I hope everyone enjoyed! And please let me know what you think about this!_


End file.
